Abstract
For integers k ≥ 2, we study two differential operators on harmonic weak Maass forms of weight 2 − k. The operator ξ2-k (resp. D k-1) defines a map to the space of weight k cusp forms (resp. weakly holomorphic modular forms). We leverage these operators to study coefficients of harmonic weak Maass forms. Although generic harmonic weak Maass forms are expected to have transcendental coefficients, we show that those forms which are “dual” under ξ2-k to newforms with vanishing Hecke eigenvalues (such as CM forms) have algebraic coefficients. Using regularized inner products, we also characterize the image of D k-1.
Similar content being viewed by others
References
Borcherds R. (1998) Automorphic forms with singularities on Grassmannians. Invent. Math. 132: 491–562
Bringmann K., Ono K. (2006) The f(q) mock theta function conjecture and partition ranks. Invent. Math. 165: 243–266
Bringmann, K., Ono, K.: Dyson’s ranks and Maass forms. Ann. Math. (in press)
Bringmann K., Ono K. (2007) Lifting cusp forms to Maass forms with an application to partitions. Proc. Natl. Acad. Sci. USA 104(10): 3725–3731
Bringmann, K., Ono, K., Rhoades, R.C.: Eulerian series as modular forms. J. Am. Math. Soc. (in press)
Bruinier, J.H.: Borcherds products on O(2, l) and Chern classes of Heegner divisors. Springer Lecture Notes in Mathematics, vol. 1780. Springer, Heidelberg (2002)
Bruinier J.H., Funke J. (2004) On two geometric theta lifts. Duke Math. J. 125: 45–90
Bruinier, J.H., Ono, K.: Heegner divisors, L-functions, and harmonic weak Maass forms. (preprint)
Bump D. (1997) Automorphic forms and representations. Cambridge University Press, Cambridge
Hejhal D.A. (1983) The Selberg trace formula for \({{\rm PSL}(2, \mathbb {R})}\), Lecture Notes in Mathematics, vol. 1001. Springer, Berlin
Iwaniec, H.: Topics in the classical theory of automorphic forms. Grad. Studies in Math., vol. 17. Amer. Math. Soc., Providence, R.I. (1997)
Lewis J., Zagier D. (2001) Period functions for Maass wave forms. I. Ann. Math. 153: 191–258
Ono, K.: The web of modularity: arithmetic of the coefficients of modular forms and q-series. Conference Board of the Mathematical Sciences 102. Am. Math. Soc. (2004)
Ono, K.: A mock theta function for the Delta-function. In: Proceedings of the 2007 Integers Conference (to appear)
Petersson H. (1932) Über die Entwicklungskoeffizienten der automorphen Formen. Acta Math. 58: 169–215
Rademacher H. (1973) Topics in analytic number theory. Springer, New York
Serre, J.-P.: Formes modulaires et fonctions zêta p-adiques, Springer Lect. Notes in Math., vol. 350. Springer, Berlin, pp. 191–268 (1973)
Serre J.-P. (1976) Divisibilité de certaines fonctions arithmétiques. L’Enseign. Math. 22: 227–260
Shimura G. (1994) Introduction to the arithmetic theory of automorphic functions. Princeton University Press, Princeton
Zagier, D.: Ramanujan’s mock theta functions and their applications [d’après Zwegers and Bringmann-Ono]. Sém. Bourbaki (2007) (in press)
Zwegers, S.P.: Mock theta functions. Ph.D. Thesis, Universiteit Utrecht (2002)
Author information
Authors and Affiliations
Corresponding author
Additional information
The second author thanks the generous support of the National Science Foundation, and the Manasse family. The third author is grateful for the support of a National Physical Sciences Consortium Graduate Fellowship, and a National Science Foundation Graduate Fellowship.
Rights and permissions
About this article
Cite this article
Bruinier, J.H., Ono, K. & Rhoades, R.C. Differential operators for harmonic weak Maass forms and the vanishing of Hecke eigenvalues. Math. Ann. 342, 673–693 (2008). https://doi.org/10.1007/s00208-008-0252-1
Received:
Revised:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s00208-008-0252-1